Furnace



Dec. 9, 1924- W. M. DUNCAN FURNACE Filed June 9, 1923 2 Sh eets-Sheet llOf Fatented Bec. 9, i924.

WILLIAM lVI. EUNCN, OLI ALIGN, ILLINOIS.

FURNAOE.

Application filed .Tune 9,

To @ZZ whom. t may com-cra.'

Be it known that I, WILLIAM M. DUN- CAN, a citizen of the United Statesof merica, a resident of Alton, in the county of Madison, State ofIllinois, have invented certain new and useful Improvements in Furnaces,of which the following is a full, clear, and exact description,reference being had to the accompanying drawings,

orming a part of this specification.

This invention relates t-o improvements in furnaces, and moreparticularly to a furnace equipped with traveling chain grates fromwhich heat is transmitted to a boiler or the like. The main object is toprovide a furnace withy a traveling grate structure which will insure anapproximately even distribution of heat throughout the width of theheating chamber of the furnace, whereby better results will be obtainedduring the operation of said furnace.

Prior to this invention, many furnaces having traveling chain grates`were each provided with but a single grate, which grate was providedwith a fuel hopperI at one of its ends. Fuel was fed to the travelinggrate from the hopper, and this fuel was burned as it was carried fromthehopper end of the grate to the opposite end thereof. It is apparentthat in the operation of a furnacl of the type mentioned, the heattransmitted to the heating chamber would not be uniform, for it is plainthat as the fuel traveled toward the discharge end of the grate saidfuel would be gradually consumed, and the intensity of the heat. risingfrom .faid fuel would be proportionately lessened.

In the furnace disclosed in the present application I employ a pair oftraveling chain grates arranged side by side, each of said travelinggrates being adapted to traiel in a direction opposite to the directionof travel of the adjacent traveling grate. By this arrangement thatportion of one grate which supports fuel which is practically consumedand is consequently not producing a great amount of heat is immediatelyadjacent to the portion of t-he associated grate which supports fuelwhich is producing the maximum amountof heat. Thus it 'is apparent thatthe pair of grates functioning as a unit transmit to the heating chamberof the furnace a body of heat which is practically uniform throughoutthe lengths of the grates, thereby greatly 1923. serial no. efiiaaimproving t-he results obtained from the furnace.

TWith the foregoing and other objects in View, the invention comprisesthe novel construction. combination and aria-gement of parts hereinaftermore specifically described and illustrated in the accompanying drawingswherein is shown the preferred. embodiment of the invention. However, itis to be understood that the invention ccmprehends changes, variationsand modifications which come within the scope of the claims hereuntoappended.

Fig. I is a fragmentary side elevation of one end of a boiler or stillequipped with a heating plant embodying the features of this invention,said heating plant being shown in sect-ion.

Fig. II is a vertical section on line II-II of Fig. I.

Fig. III is a fragmentary diagrammatical plan view of a boiler or stillequipped with my invention.

In the drawings, A designates a combustion chamber having a rear wall l,a front wall 2. side Walls 3 and l and a top wall 5, the latter beingformed by blocks 6 suspended from hanger bars 7. 8 designates supportingrods, each passing through a row of blocks 6 and also through some ofthe hanger bars 7. The hanger bars 7 are supported by channels 9 towhich they are secured by means of pins l0. as shown in Figs. I and II.The rear wall l of the combustion chamber A forms the front wall of aheating chamber B, and a llame outlet 11 is formed in the upper portionof the wall l to provide for the transmission of heat from thecombustion chamber A to the heating chamber B. l2 designates a boiler orstill forming the top wall of the` heating chamber B and adapted to beheated by the flame passing through the flame outlet ll. An arch 13 islocated adjacent to the top of the flame outlet ll and directly belowone end of the boiler. The boiler and heating chamber lie atapproximately right angles to the combustion chamber A.

C and I) designate a pair of traveling chain grates arranged within thecombustion chamber A., said grates being located side by side asillustrated in Fig. I of the drawings and being adapted to travel incourses approximately at right angles to the boiler or still 12. Thegrates C and D are arranged below the flame outlet 11 in the wall l toprovide for the passage of flame from said gratos through said flameoutlet and into the heating chamber B. is an illustration of a suitabletraveling` grate structure l employ endless rows of grate links14rpivoted together at l5, and provided with a rotary drive shaft 16 towhich a suitable number of drive wheels l? are secured. Thefuelsupporting upper portions of the endless grates travel on tracks 18and the lower portions of said grates travel on tracks 19. Tosupjiortthe rear portions of the grates each track 18 may be providedwith a curved portion 20.

The. chain grates C and D are each inounted between side walls 21 andthc walls of said chain gratos forming the side walls of a draftpassageway 23 which is interposed between said chain grates C and D, andinto which passageway air maj-.fY be forced by means of a suitableblower. Located between the side walls 2l and 22 and below the upperfuel-supporting portion. of each traveling grate is a plurality of draftboxes 2l, said draft boxes being arranged transversely of the gratas andbeing provided with open upper ends to provide for the delivery of draftthrough the beds of fuel on the upper portions of the grates. The walls22 are each provided with a plurality of draft openings 25 which permitthe passage of draft from the draft passageway 23 to the draft boxes 24,one of said openings being arranged in a wall of each draft box. ils'-sociated with each of the draft openings 25 is a rotary draft regulator26 which may be of any suitable design. rlhe rotary draft regulators 26are capable of independent operation whereby the flow of draft into eachdraft box may be regulated, and the means for operating the draftregulators associated with the grate C independently of the draftregulators associated with the grate D comprises rods 27 on each ofnv'hich one of the d aft regulators associated Awith the grate C ,ismounted. The rods Q7 pass through bearings supported. by the side walls2l and 22 of the grate D and are ach provided at its outer end with ahand wheel 29 whereby said regulators inav be rotated to permit orretard the passage of draft through the associated openings Surroundingeach of the rods 27 and rotatably arranged thereon is a tube 30, said'tube having fixed to it at one of its ends a draft regulator 26 whichis associated with one of the draft openings 25 of the grate D. Thetubes 30 are supported in the bearingsl 28 and each of said tubes isprovided at its outer end'with an operating wheel 3l similarto theoperating wheels 29 on the rods 27.. From the foregoing it is plain thatby rotating the handwheels 29 the draftv regulators associated with thegrate C may be operated independently of the draft regulators asso-`associated with the grate D being at the opciated with the grate D, andit is also apparent that by rotating the hand wheels 3l the draftregulators associated with the grate D may be operated without affectingthe draft regulators associated with the grate C.

Each traveling grate C and D is provided with a fuel hopper 32 which islocated out side of the combustion chamber A, the hopper 32 associatedwith the grate C being at one side of the furnace and the hopper positeside of the furnace and each of said traveling gratos is adapted totravel in a direction opposite to the direction of travel of theadjacent grate.

ln the operation of a Vliufnzuxe constructed in accoiidance with myinvention, the fuel passing.;` from the fuel hopper 3Q onto thetraveling grate C will be slowly consumed as it moves longitudinally ofthe combus-Y tion chamber A, so that the,l intensity of the heat risingfrom said grate will gradually diminish as said fuel approaches thedischarge end of the grate. By using a single grate this would result inan uneven heat being transmitted to the heating chamber. However, byemploying a pair of grates traveling in opposite directions, theportions of the grate D which are transmitting the maximum amount ofheat will always be immediately adjacent to the portions of the grate Cwhich are transmitting the minimum amount of heat, whereby a body ofheat of comparatively uniform intensity throughout its width will passfrom the combustion chamber to the heating chamber B, thus providing foran approximately equal distribution of heat below the boiler.

I claim:

1. A furnace provided with a plurality of travelin fuel-supportinggratesv` means associated with said traveling fuel-supportiug gratoswhereby adjacent gratos are caused to travel in opposite directions,means at one sidrof the furnace for delivering` fuel to one of a pair ofadjacent grates. and means at the other side of the furnace fordeliverinsT fuel to the other of said pair of adjacent grates.

2. A furnace provided with a combustion chamber, a heating chamber atone side of said combustion chamber. said combustion chamber having aflame outlet to Vprovide.

for delivery offlame to said heating chamber, a plurality ofv travelingfuel-supporting grates within said combustion chamber, means associated.with said traveling fuelsupporting gratos whereby adjacentgrates arecaused to travel in opposite directions, means at one side of thefurnace for delivering fuel to one grate of a pair of adjacent grates,and means at the other side of the furnace for delivering fuel to theother `grate of saidpair of adjacent gratos.

3. A. furnace provided with a combustion Laisse? chamber, a heatingchamber at one side of said combustion chamber, said combustion chamberhaving a flame outlet to provide for the delivery of flame te saidheating chamber, a boiler arranged directly above said heatingchan'iber, a pair of endless traveling chain grates arranged in saidcombustion chamber, means associated with said traveling chain grataswhereby they are caused to travel in opposite directions, means at oneside of the furnace for delivering fuel to one of said grates, and meansat the other side of the furnace for delivering fuel to the other ofsaid grates.

et. A furnace provided with a plurality of traveling fuel-supportiniygrates arranged side by side, means wherebyv adjacent fuelsupportinggrates are caused to travel in opposite directions, means at one side ofthe furnace for delivering fuel to one of a pair of adjacentfuel-supporting grates, means at the other side of the furnace fordelivering fuel to the other of said pair of adjacent fuel-supportinggrates, and means interposed between adjacent grates whereby draft issupplied to said grates A furnace provided with a plurality of travelingfuel-supporting grates arranged side by side, means whereby adjacentfuelsupporting g `ates are caused to travel in opposite directions,means at one side of the furnace for delivering fuel to one of a pair ofadjacent grates, means at the other side of the furnace for deliveringfuel to the other of said pair of adjacent grates, and neans comprisinga draft conductor interposed between adjacent grates whereby draft issupplied to said grates.

6. A furnace provided with a combustion chamber, a heating chamber atone side of said combustion chamber, said combustion chamber having` aflame outlet to provide for the delivery of liame to said heatingchamber, a boiler arranged directly above said heating chamber, a pairof endless traveling chain grates arranged side by side in saidcombustion chamber, means whereby said traveling chain grates are causedto travel in opposite directions, means at one side of the furnace fordelivering fuel to one of said traveling chain grates, means at theother side of the furnace for delivering` fuel to the other of saidtraveling chain grates, and a draft conductor interposed between saidpair of chain grates whereby draft may be supplied thereto.

7. A furnace provided with a plurality of traveling fuel-supportinggratas arranged side by side, mea-ns whereby adac-ent fuelsupportinggrates are caused to t avel in opposite directions, means at one side ofthe furnace for delivering fuel to one of a pair of adjacent grates,means at the other side of the furnace for delivering fuel to the otherof said pair of adjacent grates, means interposed between adjacentgrates whereby draft is supplied thereto, and means for separatelycontrolling the passage of draft to the individual grates.

8. A furnace provided with a combustion chamber', a heating chamber atone side of said combustion chamber, said comlnistion chamber having aflame outlet to provide for the delivery of fiame to said heatingchamber, a boiler arranged directly above said heating chamber, a pairof endless traveling chain grates arranged side by side in saidcombustion chamber, means whereby said traveling chain grates are causedto travel in opposite directions, means at one side of the furnace fordelivering fuel to one of said grates, means at the other side of thefurnace for delivering fuel to the other of said grates, a draftconductor interposed between said pair of chain grates whereby draft maybe supplied thereto, and means for separately controlling the passage ofdraft to the individual grates.

9. A furnace provided with a combustion chamber, a heating chamber atone side of said combustion chamber, said combustion chamber havin@` aflame outlet to provide for the delivery of flame to said heating cham--ber, a pair of endless traveling chain bralres arranged side by side insaid comn bustion chamber, means whereby said travcling chain grates arecaused to travel in opposite directions, means at one side of thefurnace for delivering fuel. to one of said grates, means at the otherside of the furnace for delivering fuel to the other of said grates, adraft conductor interposed between said chain gratos, a plurality ofdraft bones arranged below the fuel-supporting portion of each of saidtraveling grates, said draft boxes and said draft conductor being incommunication with each other, and means for separately controlling theflow of draft from said draft conductor to the individual draft boxes.

in testimony that I claim I hereunto aiiiX my signature.

WILLIAM M. DUNCAN.

the foregoing

